<Source: Wikipedia, http://en.wikipedia.org/wiki/Arrow_Diagramming_Method .>
Stage 1 (Activity 1 to) Stage 2 (Activity 2 to) Stage 3
Stage 4 (Activity 3 to) Stage 5 (Activity 2 to) Stage 3
E.g.
Activity1 Activity 2
(1) --------------> (2) ---------------> (3)
^
Activity 3 Activity 2 I
(4) --------------> (5) --------------------I